Means for producing a waterproof seam for polyvinyl resinous coated fabrics



HAMAN r-:r Al.

June 24, 1947. H, H; MEANS FOR PRODUCING A WATERPROOF SEAM FOR POLYVINYLRESINOUS COATED FABRICS Filed June 9, 1944 5 Sheets-Sheet 1 ZIE H. H.HAMAN ET MEANS FOR PRO June 24, 1947. AL v DUOING A WATERPROOF sEAM FORPOLYVINYL RESINOUS COATED FABRICS Filed June .9, 5 sheets-sheet 2 June24, 1947. H. H. HAMAN ET AL ,2,422,676

MEANS FOR PRODUCING A WATERPROOF SEAM FOR POLYVINYL RESINOUS COATEDFABRICS Filed June 9, 1944 f 5 sheets-sheet s June 24, 1947. H. H. HAMANETAI, '2,422,676

MEANS FOR PROD NG A WATERPROOF SEA POLYVINYL INOUS COATED FABRIC FiledJune 9, 1944 l Y neem-sheet 4 INVENTORQ v H. HAMAN l AL June 24, 1947. HY

' MEANS ,FOR PRODUOING A WATERPROOF SEAM FOR YL RESINOUS COATED FABRICS5 Sheets-Sheet 5 POLYVIN Filed June 9, 1944 l f' 1x1 'ENoR f I jaw/KMPatented June 24, 19.47

MEANS FOR PRODUCING A WATERPROOF SEAM FOR POLYVINYL BESINOUS COATEDPADRES@ Howard H. Raman and Oaks. Mich.,

John A. mais, Three assignors to The Warren Feather bone Co., ThreeDaks, Michi, a corporation of Michigan Application .rune e, 1944, semiNo. saam t claims; ici. iss-.42)

This invention relates to a means for and method of forming a waterproofseambetween two pieces of fabric coated with a polyvinyl resinouswaterproofing material.

Among the objects of the present invention is to provide a means andmethod for forming a waterproofing seam between portions of two fabricscarrying a coating of polyvinyl resinous waterproong materiai, andwherein the seam is covered with a fabric tape likewise carrying acoating of polyvinyl resinous waterproofing material, the resinouswaterproofing material contacting the seam, and wherein the taped seamis caused to travel continuously and uninterruptedly along apredetermined path while subjected to aheating and pressing operationperformed upon the seam without interrupting the travel of the seam, andin a manner to cause a flowing of the resinous material into thestitched perforations to seal the same and between the contacting facesof the fabric and the tape to form a cured, bonded, waterproofing seambetween the two pieces of fabric. A

Yet another object of, the invention resides in providing a method andapparatus for forming a waterproofing seam between two fabrics eachcarrying a coating of poLvvinyl resinous waterproofing material, whichcomprises seeming the two pieces of fabric together, applying a fabrictape carrying a coating of polyvinyl resinous waterprooflng material, tothe seam of the fabrics, causing the seamed fabric to travel alongapredetermined path while eifectinga heating and pressing operation uponthe seam-without interrupting the travel of the seam whereby to form abonded, waterproofing union or seam between the fabrics.

Yet another object of the invention resides in providing heating andpressing means for form ing a waterproofed fabric seam wherein thefabric seam is fed between the heating. and pressing means, at least aportion of which is sectionally formed with respect to the crosssectional area of the seam so as to exert a uniform pressure upon theseam despite differences of thickness in the seam. n

Yet another object of the invention resides in providing rotatablepressing ro11s,-at least one of which is heated, and between which theseemed fabric to be waterproofed is heated and pressed and by which itis continuously fed therebetween to effect the seam formation. V

Yet another object of the invention resides in providing means fordriving each part of the sectional heating and pressing rolls to effectthe feeding of the seamed fabric therebetween while permitting therelative movement of these sections of the roll to correspond to variantthicknesses in the seam. Y

yYet another object of the invention resides in providing 'a methodforming a seamed fabric.

Other and further objects of the invention will be apparent from aperusal of the following specification when taken in connection with theaccompanying drawings wherein:

Figure l is a side view oi' the machine, with por-1 tions being shown incross section;

Figure 2 is a fragmentary detail view taken on the line 2-2 of Figure 1:

Figure 3 is a vertical sectional view taken on the line 8-3 of Figure i;

Figure 4 is a detail fragmentary view showing the scraper blade inrelation to one of the pressing rollers; 0

Figure 5 is a detail plan sectional view taken on the line 5 5 of Figure1;

-Figure 6 is a detail plan sectional view taken on the line t-e ofFigure 1;

Figure 7 is a fragmentary detail sectional view:

Figures 8, 9 and 10 are fragmentary detail sectional views showing thevarious positions of the rolls and the material as it is fed through themachine: and

Figures 11, 12 and 13 are enlarged cross sectional views through thematerial, showing the progressive steps as it is being treated.

The mechanism of the present invention is utilized to provide a bonded,sealed, waterproof seam, and preferably a stitched seam. interconnectingtwo waterproofed fabric pieces which may be used for making a raincoat,a large tarpaulin, or any type of water-shedding or waterproof materialthat requires a seam. In the present illustration lwe have shown th'efabric as two pieces of fabric which are impregnated with a, waterproofcoating of plasticized polyvinyl chlo- .side on which the coating isapplied has a smooth.

shiny, lustrous surface, whereas the other side has a. dull, roughsurface. The particular invention is concerned with providing a seam tounite together two of Athese pieces of waterproofed fabric, and as shownin Figure 11, the fabric piece A is shown as provided with the polyvinylrelsinous coating B, and as will be hereinafter set ing of polyvinylresinous material C. This fabric is to be united to a second fabricpiece D which likewise carrieson one 'face the polyvinyl 'resinouswaterproofing coating E. 'I'his fabric piece D is provided with amarginal coating F of polyvinyl resinous waterproofing material ofsubstantially the same type aS the coating E. These two fabric pieces Aand D are laid together as shown in Figure 1l, with their resinouscoatings facing outwardly, and are then stitched together as at G, thestitching passinglcompletely through the coated fabrics. The stitchingis made preferably after the coating F is dried. Next the two fabricends are separated and are placed in substantially a common plane, asshown in Figure l2. The connecting stitching G forms a pivot for the twolayers so that the short end H of the fabric piece A will overlie theshort end I of the fabric piece D, and the fabric piece D will overlieone end of th'e stitching G. The opposite end of the stitching G willappear at the surface of the upper side of the fabric piece A.' Thefabric piece D is provided with the fold J. It will be noted that inthis last arrangement the polyvinyl resinous coating F will lie betweenthe fold I and the fabric piece D below the stitches. This' resinousmaterial functions under subsequent heat and pressure to ow and sealythe lower ends of the stitched perforations shownin Figure 12, and inaddition serves to adhere the ap I to the body portion of the fabric D.This nowing of the polyvinyl material is due to the fact F is applieddirectly to that the cement coating the main coating E of the fabricDbetween the flap I and the fabric D where th'e stitching takes place,so that there is ample polyvinyl resinous material to seal the stitchingperforations at this point. After the two fabrics A and D are arrangedas shown in Figure 1 2, they upper sides of the fabric A and fabricD,vas shown in. Figure 12, are then given a coating K of polyvinyl res-`inous cement which-is applied directly to the polyvinyl resinouscoatings B and E of said fabric pieces A and D. Thus the entire marginalsurfaces of the fabrics A and D at the seam and on each side of theseam. original coatings B and E, buty also include a superimposedpolyvinyl coating of cemen The seam is now ready for the application ofthe tape L, which tape is a fabric,tape carrying a coating of polyvinylresinous waterproofing material, preferably of the same material withwhich the fabrics A and D are coated. This fabric tape, in fact, ispreferably of thfe same material as A and D, except that if desired itmay be a lighter weight fabric. 'Ihis tape L is applied over the seam,as shown in Figurel 3, with the polyvinyl coating M on the tape facedownward. Attention is called to the fact that this polyvinyl coating M.contactingly overlies the coating K of the seam and adjacent coatedparts of the fabric A and D, and the fabric tape directly overlies theuper edge of th'e stitching G. The fabric seam with the tape overlying,as shown in Figure 13, is now ready to be run through the heat andpressure devices constituting the device ofthe present invention,whereby the polyvinyl resinous material is caused to flow under heat andpressure to plug the stitching perforations through the include not onlythe forth, being provided with a marginal zone coat` after will setpermanently. 4The twoy fabrics thus seamed, and-with the tape overlyingas shown in Figure i3, are laid upon the table 2 and fed between thepressing rolls as hereinafter described. In general, these pressingrolls comprisefvnpper and low er `rolls vsuitably pressed together,preferably by spring mechanism, to produce therequiredipressuretherebetween, and one of these rolls is heated to asuitable temperature while the other -roll is maintained at roomtemperature in order to -dissipate the heat `and to speed up the curingoperation.' These rolls are metal rolls g with polishedsurfaces, andthey-are made in sec- 'tions with lthe periph'erics relatively movable,

whereby to exert a uniform cross sectional pressure upon the fabric andtape as the rolls feed the fabric therebetween ina continuous action,and at the same time heat and press the fabrics and tape together toeffect the owing of the polyvinyl material, its curing, and to permitits subsequent setting. In the present instance the seaming operation iscarried out in a` continuous manner and with considerablerapidity,preferthe peripheries of these rollers ably by driving the pressingrolls, thereby causing them not only to do the pressing and heating, butto feed the length of material therethrough. Referring now to thedrawings in detail, the device comprises an ordinary table 2 mounted onlegs 4 and forming a support or foundation for the mechanism which ismounted on the table or other support. The mechanism comprises a framemember having two side legs 6 and v8 and a horizontally disposed topframe member l0. Supported from the horizontal top framemember i0 is abracket arm'` I2 which rotatably supports a reel `I4 upon which iscoiled the tape L, the nature of which will-be hereinafter described. Aspring iB surroundlng the central shaft of the reel provides asuiiicient friction to keep the `tape taut, as is well known in the art.i The cross head lll supports two depending arms 20 and 22 (see Fig; 3)the bottom portions of which provide bearings 24 and 26 for ahorizontally disposed shaft'28. 'I'his'cross head l0 also supports asupporting plate'f30 which carries bearings 32and 34 for vertical shafts36 and 38. These shafts support fthe heating and pressing rolls 40 and42 hereinafterreferred to. l The top of the table is provided withfa`pair of openings 46 and 48 through which'project the peripheries of apair of roller platens 50 and 52,

and 52 extending through these openings and lying in opposition to theupper pair of rollers 40- and 42.

Means is provided for driving the rollers so that they not only heat andpress the material therebetween but likewise feed it along at a constantrate so that the heating effect on the seam will be uniform. In additionthese rollers are formed of sections whereby: the pressing 'effectacross the entirev section of theseam will be uniform despitediiferences in thicknessof the fabricy and to' unite lthe tape and thefabrics to each.

other lto provide a terproof seam, `which during the 'heating pressingoperation will cure, and shortly theresealed, bonded,vk strong, wa- ,lf

and

vgear 63 loosely mounted upon. A worm gear in turn meshes-with awoixriyhee l`yrvl` seam. l In accordance with the foregoing, beneathv the tableis mounted a motor 54, the shaft of A,whiclpw drives the bevel gear 56which in turn'f another bevel gear 58 on a shaft 60. This shaft 60 inturn carries a clutch 62 adapted to be sh ed, by a clutch shifter 64having a clutch shlif handle 66, into clutching relationwitha or? meshaft so i la "1o pinned to a shaft blocks 14 and 16, see

I2l mounted in'b Figure 6. This shaft has .vided with a gear 90 similarto gear 84, which meshes with the gear 92 fastened to roller section50A. Wheel section 50B and its gear 86 are mounted on a cross shaft 94carried by bearings 96 and 98, and wheel section 50A and its gear 92 aremounted on a shaft |00 carried in bearings |02 and |04. Each of thesebearings consists of a slidable block |06 which is spring pressedupwardly by means of a spring |08 to cause the shafts |00 and 94 to bemoved upwardly, and causing the rollers 50A and 50B to be pressed upagainst the lower periphery of the upper roll 40. In order to adjust theamount of pressure that is on these blocks the screw adjustments areprovided.

'I'he lower roller 52 with its gear 88 is mounted upon a shaft ||2.whichis also mounted in spring pressed bearing blocks |06 which are likewiseadjustably positioned in bearings ||4 and H8 to cause the roller 52 topress upwardly against the periphery of the upper roller 42.

Means is provided for raising the front and rear upper rollers so as tofeed the fabrics and their seam between the upper and lower rollers.

To this end the upper rollers 40 and 42 are each carried by the yokes I8and |20 in turn mounted on shafts 36 .and 38 which are normally springpressed downwardly by springs |25 and |21. The uDDer ends of theseshafts 36 and 38 have pinned thereto as at |22 and |24 cams |25 and |28,each of which has a handle |30 whereby upon lowering the handles thecams wipe against the bosses 3 2 and 34 whereby to raise the shafts andhence the rollers 40 and 42.

In addition. the shaft 28 terminates in a gear |44 pinned thereto, whichin turn meshes with two gears |46 and |48 integrally carried by each ofthe upper rolls 40 and 42 respectively, whereby said rolls arepositively rotated by the rotatable,

gear |44 on the shaft 28.

' Ihis would take place, for instance, at the lshoulder seam of araincoat. This relative movement of the roller sections A and 5081s dueto the spring pressed bearing blocks |05, as shown in Figure 3.

Means is provided for accurately guiding the seam with respect to thecross section of the roll so that the thicknesses accurately adjustthemselves and correspond'to the cross sectional area of the rolls. Thisis accomplished by providing the upper part ofthe table bed with a.

laterally adjustable guide plate |80. This guiding plate has an upturnedguide edge |62 which contacts the folded end J of the seam, see Figure13, and thus lines up this part of the seam with the mostvdeeplyrecessed portion 4| of the heating and pressing roll, see Figure 8.

It is understood that the upper and lower presser rolls 42, 50 and 52are not heated. The top roll 42 has an annular cross sectional recesssimilar to that of the top roll 40 whereas the bottom roll 52 has aplain periphery, as shown in Figure 6. These rolls, as heretoforestated, are driven together to not only assist in feeding the seamedfabric and tape therebetween, but also to exert an additional pressingaction upon the seam as it is fed through the rollers. The rear rollers42 and -52 smooth and even out the seam and apply any additionalpressure to cause the sealing eifect to be completed, without at thesame time heating the fabric seam and tape. As the seam leaves the rearset of rollers 42 and 52 the material has cooled suiliciently so thatthe seam is set. The setting of the polyvinyl resinous material isencouraged and speeded up by the contact of the seam with the unheatedrollers 42, 50, and 52.

The springs 318 and 38 which urg'e the upper rolls downwardly arearranged to provide a pressure of substantially thirty pounds, more orless, per square inch upon the seamed fabric as it is passed between theroller and the heating means for the upper roll .is arranged to producea temperature of substantially 180 F., more or less. The spring tensioncan be more or less than thirty pounds per square inch, according t0 therequirements of the material to be processed.

Means is provided for heating the roller 40 and this comprises anelectric heater coil |50 located internally of the roller 40 andconnected to a proper electrical circuit for heating the roller atdesired times and as it rotates. In addition the upper roller isprovided with a scraper |52 mounted upon a bar |54 which moves with theraising and lowering of the yoke I8. This bar also carries on its |55.

opposite end a tape guide As shown in Figure 4, the scraper is suitablyv conformed at its bottom to ride in the various annular grooves orshoulder` portions of the upper roll. yAs shown in Figure 8, this upperroller is grooved in cross section to conform to the differentthicknesses of the seam in order to get an even pressure upon each crosssectional area of the seam, and as shown in Figures 9 and 10,

this roller when in pressing and heating engagement with the fabrics andtape, presents hard metallic surfaces between which the tape and fabricpieces of the seam are pressed. By refer- "ence to Figures l9 "and 10ity will be'seen thatithe two sections of the roller may yield one withrespect to the other. to accommodate the varying thicknesses of theseam, such for instance v as where a cross seam forms a part of theseam.

In the operation of the device, when the motor is put into operation andthe seam, as shown in Figure 13, is fed between the rolls, the rollswill be operated at a speed of substantially four revolutions perminute, thereby to feed the seamed fabric therebetween and therethroughat a constant uniform rate. The heated roll 40 will press the seamagainst the lower roll 50 over a very -narrow.' area. of contact ofabout one-eighth of an inch, extending entirely across the seam. 'Iheheating eifect is at such temperature as to effect the curing ot thepolyvinyl resinous material in the short space of time that the heatedrroll is in contact with the fabric and is pressingr against the lowerroll. The scraper |52 serves to scrape of! any resin which may tend toadhere to the roll, and the lower roll 55 which is at room temperaturetends to dissipate the heat quickly so as to condition the seam forrapid setting as it passes from between the rolls 40 and 50. Withoutthis relatively cooler surface of the lower roll 50 the material at theseam would take longer to cure. It is to be noted that the upperandlower'rolls are positively driven at substantially the same speed,whereby to prevent any slip therebetween which would tend to ruin theseal and the tape and create an objectionable section. Y

` for interconnecting two pressing the seam sulciently to The fabric andthe fabric tape may be coated with any type of waterproofing materialdisclosed in 'an application filed by Howard H. Haman and Charles E.Whalen contemporaneously herewith entitled "Method of sealing togethertwo pieces of waterproof fabric, and the. seam formed thereby," SerialNo. 539,456, filed June 9, 1944, now Patent No. 2,406,830, datedSeptember 3, 1946. Wherever the expression polyvinyl resinous materia isused it is meant to include all substances disclosed in saidapplication.

Obviously .the invention is not limited to the specic details ofconstruction disclosed herein but is capable of other mcdications andchanges without departing from the spirit and scope of the appendedclaims.

" Having thus described our invention, what is claimed as new anddesired to be secured by Letters Patent is:

l. An apparatus for forming a waterproof sacaste means being formed ofrelatively yieldabie sections, whereby to provide a uniform pressurethroughout the cross sectional area of the pressing means irrespectiveof the variations in thickness of the seam, and one of said hard facedarcuate surfaces being heated.

i 3. An apparatus for forming a. waterproof seam for interconnecting twofabrics coated with polyvinyl resinous waterproofing material and havinga row of stitching passing through marginal portions of said coatedfabrics, and wherein a fabric i tape coated with polyvinyl resinousmaterial overseam for interconnecting two fabrics coated with ipolyvinyl `resinous waterproofing material and having a row of stitchingpassing through marginal portions of said coated fabrics, and wherein afabric'tape coated with polyvinyl resinous material overlies thestitched seam with the coating of the tape contacting the stitched seam,comprising in combination a support, means on said support foruninterruptedly feedingthe seamed and taped fabric along a predeterminedpath relative to said support, and means mounted on said.suppot in thepath of ing to seal the same and to cure that portion of the polyvinylresinous material between the contacting fabrics and the tape wherebyupon re- -moval of said heat .and pressure said seam subsequently setsand provides a bonded waterproofing junction between the two fabrics,said heating and pressing means comprising opposed, hard faced, arcuatesurfaces' moving at the same rate of travel as the travel of the seam,one of said arcuate pressing means yieldable sections, wherebypressure-throughout the the pressing means irrespective of thevariations in thickness of the seam.

2. An apparatus for forming a waterproof seam fabrics coated withpolyvinyl resinous waterproofing material, said seam includingoverlapping marginal portions of said coated fabrics of variantthicknesses, and wherein a fabric tape coated with polyvinyl resinousmateria overlies a portion of the seam -and with the coating of the tapecontacting one of the fabrics, comprising in combination a support,means on said' support for uninterruptedly feeding the seamed and tapedfabric' along a predetermined to provide uniform Y path relative to saidsupport, and means mounted on said support in the path of movement ofthe travelling seam of said fabrics for heating and cause the flow of aportion of the polyvinyl resinous material to seal and to cure thatportion of the polyvinyl resinous material between the contactingfabrics and the` tape whereby upon removal of said heat and pressuresaid seam subsequently sets and provides a bonded waterproofing junctionbetween the two fabrics, said heating and pressing means comprisingopposed hard faced arcuate surfaces moving at the same rate of travel asthe travel of the seam,v one ofsaid areuatevpressing being formed of.relatively cross sectional area of lies the stitched seam with thecoating of the tape contacting the stitched seam, comprising incombination a support, means on said support for uninterruptedly feedingthe seamed and taped fabric along a predetermined path relative to saidsupport, and means mounted on said support in the path of movement ofthetravelling seam of said fabrics for heating and pressing the seamsuiliciently to cause the flow of a portion of the polyvinyl resinousmaterial at least partially into the perforations of the stitching toseal the same and to cure that portion of the polyvinyl resinousmaterial between the contacting fabrics and the tape whereby uponremoval of said heat and pressure said seam subsequently sets andprovides a bonded waterproofing junction between the two fabrics, saidheating and pressing means comprising opposed metal rollers, means forremovement of the travelling seam of said fabrics for heating andinterruptedly Vsame uniform speed whereby the one of said rollers beingheated, and one of said 'ollers being composed of relatively yieldablesecions.

4. An apparatus for forminga waterproof seam for interconnecting twofabrics coated with polyvinyl resinous waterproofing material and havinga row of stitching passing through marginal portions of said coatedfabrics, and wherein a fabric tape coated with polyvinyl resinousmaterial overlies the stitched-seam with the coating of the tapecontacting the stitched seam, comprising in combination a support, meanson said support for uninterruptedly feeding the seamed and taped-fabricalong a predetermined path relative togsaid support, and means mountedon said support in the path of movement of the travelling seam of saidfabrics for heating and pressing the seam sufficiently to cause the flowof a portion of the polyvinyl resinous material at least partially intothe perforations of the stitching to seal the same and to cure thatportion of the` polyvinyl resinous material between the contactingfabrics and the tape whereby upon removal of said heat and pressure saidseam subsequently sets and provides a .bonded waterproofing junctionbetween the two fabrics, said heating and pressing means comprising twopairs of opposed rollers, meansfor rotating each roller of a pair at thebetween said rollers will be caused to travel un- A at a uniform ratetherethrough, one of said rollers being heated, and one of said rollersbeing formed of relatively yieldable Asections to provide uniformpressure along the width of the seam, irrespective of variantthicknesses transversely of the seam.

5. An apparatus for forming a waterproof seam for interconnecting twofalbrics coated with polyvinyl resinous waterproofing material andhaving a' row of 4stitching passing through `marginal portions of saidcoated fabrics, and wherein a fabric tape 'coated -with polyvinylresinous material overlies the stitched seam with the coating of thetape contacting the stitched seam, comfabric seam fed marginal portionsthereof,

prising invcombination a suppport, means on said support foruninterruptedly feeding the seamedand taped fabric along a predeterminedpath relative to said support, and means mounted on said support in the'path of movement of the travelling seam of said fabrics for heating andpressing the seam suillciently to cause the iiow of a portion of thepolyvinylv resinous material at least partially into the perforations ofthe stitching to seal the same and to cure that portion of the polyvinylresinous material between the contacting fabrics and the tape wherebyupon removal of said heat and pressure said seam subsequently sets andprovides a bonded waterproofing Junction betweenthe two fabrics, saidheating and pressing means comprising two pairs of rolls mounted on saidsupport and between which the seam of the fabric is introduced wherebythe between which the fabric is rst fed will rolls contact andthereafter feed the fabric sequentially through the second set of rollsand whereinafter both sets of rolls serve to feed the fabric at auniform rate of travel along a predetermined path, one of the rolls ofthat pair which the fabric first contacts during the feeding processbeing heated, and the opposed roll being formed of sections extendingtransversely of the width of the seam, said sections being relativelyyieldable with respect to each other and with respect to the firstmentioned roll, and spring means'for pressing all of said rolls towardeach other.

6. In a device of the class described, in combination with a supporthaving a relatively fiat top. two pairs of rolls mounted on said tablewith the peripheries between said pairs of rolls lying substantiallyinthe plane of the table top whereby two fabrics, each coated withpolyvinyl resinous material and stitched together along are fed betweena first pair of said rollers, a reel mounted on said support carrying aroll of fabric tape having a facing of polyvinyl resinous waterproofingmaterial, means for feeding the tape from said reel into position tooverlie the stitched seam of the two fabricel with the taped coatingcontacting the seam whereby said tape is adapted to contact-' inglyoverlie and cover said seam and passes with said seam between said firstmentioned rollers, there being means for uniformly driving all of saidrollers at a constant, identical rate of speed whereby the taped l0 Re.20,789

between saidnrsc and then said second set of rollers whereby to causethe taped seam to travel through all of said rollers at a uniform rateof speed, spring means for forcing said rollers' together to exert apressure upon said seam as it passes through said rollers, and means forheating only one of said first mentioned set of rollers, the lower oneof said first pair of rollers including relatively yieldable sections.

7. In a device of the class described, in combination with a supportproviding a relatively at feeding surface, there being openings in saidsurface, upper and lower pairs of metallic rolls mounted in oppositionabove and below said openings whereby the peripheries of said rolls liesubstantially in the plane of said fiat surface, means for resilientlymounting one of said pair of rolls so as to constantly pressV toward theperipheries of said other rolls of a pair, means for rotating each ofsaid rolls/at the same uniform rate of rotation whereby material fedbetween said rolls will be engaged and fed thereby through said rolls atan uninterrupted, uniform rate of travel, means for releasing saidresiliently mounted rolls whereby to admit material therebetween to befed, means forv heating one of the rolls oi' each pair of" rolls, therolls of each pair that are opposite the heated rolls being formed ofrelatively yieldable sections extending transversely of the width of theroll. HOWARD H1 HAMAN.

JOHN A. RITZLER.

REFERENCES CITED Name Date Bergstein July 12, 1938 Spanel July 6, 1943Vincent Feb. 29, 1944 Hosneld Mar. 14, 1944 FOREIGN PATENTS country DateGreet Britain oct. 17, 1935 Number Number A. P. C.

seam is fed uninterruptedly 391,802, pilished April 27, 1943.

